These new “secondary” forests are emerging in Latin America, Asia and other tropical regions at such a fast pace that the trend has set off a serious debate about whether saving primeval rain forest — an iconic environmental cause — may be less urgent than once thought. By one estimate, for every acre of rain forest cut down each year, more than 50 acres of new forest are growing in the tropics on land that was once farmed, logged or ravaged by natural disaster.


This article from the New York times really gets me. The gist is that due to economic conditions in the tropical countries many people are moving to the city and abandoning arable land. This land is then growing back into forest and acting as a carbon sink. Apparently, according to the article, there is a "debate" among scientists as to whether or not we should decrease our efforts to save tropical forests since these new second growth forests may be sucking up enough carbon to make up for the lost primary forest.

This is wrong on many levels, maddeningly wrong. First, I doubt that there is any serious debate on this topic. However, the news must make a story so they find some wingnut and twist his story into a debate. This happens way too often and is die in large part to the lack of qualified science editors in news organizations.

For a primer and some great pictures of the difference between primary and secondary tropical forest visit this site.

Second, there is a clear distinction, even in temperate forests, between primary (old growth) forest and secondary forest. Yes, it is true that secondary forests are carbon sinks, they may even suck up carbon at a faster rate than old growth due to their higher growth rate. However, the forest is very different. It only has one canopy, there is a marked decrease in species richness (marked being often greater than 50% fewer species of all animals, plants and birds), it is also more susceptible to fire (a previously virtually unknown problem in the wet tropics until we started cutting down the forest at the clip we have become used to). Also, it is not guaranteed to proceed into primary forest, and even when it does develop taller trees and multistory canopy it is much less diverse. Worse, some forests have a very delicate balance that, if disturbed, would likely never return. This includes things such as Varzea forest in the Amazon in which the annual flooding has induced fish, bird, insect, tree and mammal species to develop complex interrelationships. These forests will never come back the way they were if they are destroyed.

Third, who says that economic conditions won't change. Up until recently it was easy to get a job, now with the economic downturn that may change drastically. For poor peasants in the third world it is better to be a subsistence farmer than a poor, homeless bum in a city. People will begin to recultivate these areas. Large farms will probably do well. Commodity prices could easily spike again as they did last winter in the midst of the current recession. Also, commodities are fairly stable and concrete compared to other investments. I'd rather have an acre of fertile tropical soil than a $100,000 mortgage derivative investment at this point. To divert money from saving primary forest in the hope that abandoned land will stay as forest is a pipedream.

This is to say nothing of the need for species diversity. If this is ignored completely in favor of simply looking at this from a carbon balance perspective we've lost the battle. We are currently causing one of the greatest extinctions in the histroy of the world. Like it or not we are tied into the food web, the fewer species there are the less stable that web becomes. Similarly, we lose the opportunity to sustainably exploit these resources in ways we have yet to discover. The argument is tired and old but there may indeed be great medicinal value in some of the species in tropical forests. And this is all glossed over by our moral imperative to keep our world safe for our children.

I would like to know the full story on this. I doubt that there is truly a large debate in the scientific community, although I would say there is certainly a good amount of righteous indignation toward this Joe Wright guy. His position is completely untenable and lacking any long-term thinking. If we were to take him seriously we would lose one of the greatest treasures and greatest resources this world has to offer. If this story did indeed paint Joe Wright and the controversy in the proper light he is a stooge to be ignored, not a serious force in tropical science or conservation.